@for $i from 1 through 100 {
    [w#{$i * 5}], .w#{$i * 5} {
        width: #{$i * 5}px;
    }
}

[b-box], .b-box {
    box-sizing: border-box;
    -moz-box-sizing: border-box;
    -webkit-box-sizing: border-box;
}

[block], .block {
    display: block;
}